BCH394P BCH364C 2019
BCH394P/BCH364C Systems Biology & Bioinformatics
Course unique #: 54044/53945
Lectures: Tues/Thurs 11 – 12:30 PM in JGB 2.202
Instructor: Edward Marcotte, marcotte @ icmb.utexas.edu
- Office hours: Wed 11 AM – 12 noon in MBB 3.148BA
TA: Caitie McCaffery, clmccafferty @ utexas.edu
- TA Office hours: Mon 11-12/Fri 2-3 in NHB 3.400B atrium (or MBB 3.128B) Phone: 512-232-3919
Lectures & Handouts
Mar 14, 2019 - Motifs
- Today's slides
- Due March 25 by email - One to two (full) paragraphs describing your plans for a final project, along with the names of your collaborators. This assignment (planning out your project) will account for 5 points out of your 25 total points for your course project. Here are a few examples of final projects from previous years: 1, 2, 3, 4, 5 6 7 8 9 10 11 12 13 14
- NBT Primer - What are motifs?
- NBT Primer - How does motif discovery work?
- The biochemical basis of a particular motif
- Gibbs Sampling
- FYI, we stopped the nanopore sequencing run we started pretty soon after class, but even in a relatively short time (<30 min), our longest read (sequencing randomly shorter DNA fragments from a 40kb phage genome) was >20 kb.
Mar 12, 2019 - Live Demo: Next-next-...-generation Sequencing (NGS) by nanopore
- Homework #3 (worth 10% of your final course grade) has been assigned on Rosalind and is due by 11:59PM March 25.
- We're going to be live-demoing a nanopore single molecule DNA sequencer in class, assuming all goes well. Specifically, we'll be using an Oxford Nanopore MinION sequencer, which differs substantially from these major alternatives:
- Youtube video of Illumina/Solexa Sequencing by Synthesis
- Youtube video of Pacific Biosciences single molecule sequencing by synthesis in zero mode waveguides
- Here's Oxford nanopore's own videos explaining the tech. DNA sequences are collected first as electrical traces. A big breakthrough was learning to convert these traces to DNA nucleotide sequences using hidden Markov model based algorithms very similar in spirit to those we've already talked about in class (e.g., as in this open source HMM-based nanopore base-caller). The latest base-callers are moving towards neural network algorithms.
Mar 7, 2019 - Genomes II
- We're finishing up the slides from Feb. 28. Note that we give short shrift to read mapping/alignment algorithms, of which there are now a very long list. Here's an interesting discussion by Lior Pachter of the major developments in that field.
- Here is an excellent explanation of how the BWT relates to a suffix tree and enables fast read mapping to a genome
- If you want a more detailed explanation, the BWA paper more formally describes how the Burrows–Wheeler transform can be used to construct an index.
- & here are two more examples of using the BWT for indexing: 1 2
- Plus: "I have some troubling news...the human reference genome is incomplete", breaking prepublication results on the telomere-to-telomere assembly of a complete human X chromosome from Karen Miga and Adam Phillippy, presented at the AGBT 2019 conference last week.
Mar 5, 2019 - Guest Lecture: Anna Battenhouse, NGS Analysis Best Practices
- Practical advice and best practices for NGS mapping and analysis
- Today's slides
Feb 28, 2019 - Genome Assembly
- Today's slides
- A gentle reminder that Problem Set 2 is due by 11:59PM March 6
- Also, next Tuesday will be the first of our guest lecturers, Anna Battenhouse, on practical aspects of genome sequencing/assembly
- DeBruijn Primer and Supplement
- If you would like a few examples of proteins annotated with their transmembrane and soluble regions (according to UniProt) to help troubleshoot your homework, here are some example yeast protein sequences.
- From last time, some definitions of sensitivity/specificity & precision/recall. Note that the gene finding community settled early on to a different definition of specificity that corresponds to the precision or PPV in other fields. Other fields define specificity as the true negative rate.
Feb 26, 2019 - Gene finding II
- We're finishing up the slides from Feb. 21
- Peer-led open coding hour has been resurrected! Wed 12:30-1:30 in the MBB 2nd floor student lounge (the newly revamped eating space)
Feb 21, 2019 - Gene finding
- We'll finish HMM slides from Feb 19, then start today's slides on gene finding
- Some science news of the day: "In the past 12 months Americans have searched for Python on Google more often than for Kim Kardashian"
- For a few more examples of HMMs in action, here's the recent paper on sequencing the human genome by nanopore, which used HMMs in 3-4 different ways for polishing, contig inspection, repeat analysis and 5-methylcytosine detection.
- The UCSC genome browser
Problem Set 2, due before midnight Mar. 6, 2019:
- Problem Set 2.
- You'll need these 3 files: State sequences, Soluble sequences, Transmembrane sequences
Reading (a couple of old classics + a review):
Feb 19, 2019 - HMMs II
- We're finishing up the slides from Feb. 14.
- I was just pointed to this great interactive visualization of Markov Chains, by Victor Powell & Lewis Lehe. It's worth checking out to build some intuition.
- A non-biological example of using log odds ratios & Bayesian stats to learn the authors of the Federalist Papers
Feb 14, 2019 - Hidden Markov Models
- Happy Valentine's Day!
- Don't forget: Rosalind Homework #2 (worth 10% of your final course grade) is due by 11:59PM February 20.
- Modern Statistic for Modern Biology, by Susan Holmes and Wolfgang Huber, discussed last time. It's currently available online and due to be released on dead tree in the US in April. (FYI, all code is in R.)
- Today's slides
- HMM primer and Bayesian statistics primer #1, Bayesian statistics primer #2, Wiki Bayes
- Care to practice your regular expressions? (In python?)
Feb 12, 2019 - Biological databases
- Homework #2 (worth 10% of your final course grade) has been assigned on Rosalind and is due by 11:59PM February 20.
- Science news of the day: Does gum disease cause Alzheimer's?
- Just a note that we'll be seeing ever more statistics as go on. Here's a good primer from Prof. Lauren Myers to refresh/explain basic concepts.
- Today's slides
Feb 7, 2019 - BLAST
- Science news of the day: Yet more CRISPR baby news!
- Our slides today are modified from a paper on Teaching BLAST by Cheryl Kerfeld & Kathleen Scott.
- The original BLAST paper
- The protein homology graph paper. Just for fun, here's a link to a stylized version we exhibited in the engaging Design and the Elastic Mind show at New York's Museum of Modern Art.
Feb 5, 2019 - Sequence Alignment II
- We're finishing up the slides from Jan. 31.
- Science-ish news of the day: The Dance Your Ph.D. contest is on!
- Fact and Fiction in Sequence Alignments
- Dynamic programming primer
- An example of dynamic programming using Excel, created by Michael Hoffman (a former U Texas undergraduate, now U Toronto professor, who took a prior incarnation of this class)
- A few examples of proteins with internally repetitive sequences: 1, 2, 3
Jan 31, 2019 - Sequence Alignment I
- For those of you who might be interested, Rosalind is having a Bioinformatics Contest. Sign up runs until Feb. 2, the qualification round is Feb. 2-10, and Feb. 23 is the final round, with 24 hours to solve as many problems as you can. First prize in 2019 is to get your genome (exome) sequenced or get your own nanopore sequencer!
- Today's slides
Problem Set I, due before midnight Feb. 11, 2019:
- Problem Set 1
- H. influenzae genome. Haemophilus influenza was the first free living organism to have its genome sequenced. NOTE: there are some additional characters in this file from ambiguous sequence calls. For simplicity's sake, when calculating your nucleotide and dinucleotide frequencies, you can just ignore anything other than A, C, T, and G.
- T. aquaticus genome. Thermus aquaticus helped spawn the genomic revolution as the source of heat-stable Taq polymerase for PCR.
- 3 mystery genes (for Problem 5): MysteryGene1, MysteryGene2, MysteryGene3
- *** HEADS UP FOR THE PROBLEM SET *** If you try to use the Python string.count function to count dinucleotides, Python counts non-overlapping instances, not overlapping instances. So, AAAA is counted as 2, not 3, dinucleotides. You want overlapping dinucleotides instead, so will have to try something else, such as the python string[counter:counter+2] command, as explained in the Rosalind homework assignment on strings.
- BLOSUM primer
- The original BLOSUM paper (hot off the presses from 1992!)
- BLOSUM miscalculations improve performance
- There is a good discussion of the alignment algorithms and different scoring schemes here
Jan 29, 2019 - Intro to Python #2
- We'll be finishing Python slides from last time, plus Rosalind help & programming Q/A, maybe a glimpse of next lecture.
- Science news of the day: A 500 year experiment, with a nice commentary in The Atlantic
- Statistics in Python
Jan 24, 2019 - Intro to Python
- REMINDER: My email inbox is always fairly backlogged (e.g., my median time between non-spam emails was 11 minutes when I measured last year), so please copy the TA on any emails to me to make sure they get taken care of.
- Today's slides
- Python primer
- E. coli genome
- Python 2 vs 3?. For compatibility with Rosalind and other materials, we'll use version 2.7. The current plan is for Python 2.7 support to be halted in 2020, but there is some hope (wishful thinking?) that Python 4 will be backwards compatible, unlike Python 3. Regardless, you're welcome to use whichever version you prefer, but we'll use 2.7 for all class explanations in the interests of simplicity and consistency. For beginners, the differences are quite minimal.
Jan 22, 2019 - Introduction
- Science news of the day (& a reminder of the importance of ethics in science!): Chinese authorities say world's first gene-edited babies were illegal
- Today's slides
- Some warm-up videos to get you started on Python (2 not 3, unless you pay for an upgrade): Code Academy's Python coding for beginners
- Khan Academy has archived their videos on Python here
- We'll be conducting homework using the online environment Rosalind. Go ahead and register on the site, and enroll specifically for BCH394P-BCH364C-Spring2019 using this link. Homework #1 (worth 10% of your final course grade) has already been assigned on Rosalind and is due by 11:59PM January 31.
- A useful online resource if you get bogged down: Python for Biologists. (& just a heads-up that some of their instructions for running code relate to a command line environment that's a bit different from the default one you install following the Rosalind instructions. It won't affect the programs, just the way they are run or how you specific where files are located.) However, if you've never programmed Python before, definitely check this out!!!
Syllabus & course outline
An introduction to systems biology and bioinformatics, emphasizing quantitative analysis of high-throughput biological data, and covering typical data, data analysis, and computer algorithms. Topics will include introductory probability and statistics, basics of Python programming, protein and nucleic acid sequence analysis, genome sequencing and assembly, proteomics, synthetic biology, analysis of large-scale gene expression data, data clustering, biological pattern recognition, and gene and protein networks.
Open to graduate students and upper division undergrads (with permission) in natural sciences and engineering.
Prerequisites: Basic familiarity with molecular biology, statistics & computing, but realistically, it is expected that students will have extremely varied backgrounds. Undergraduates have additional prerequisites, as listed in the catalog.
Note that this is not a course on practical sequence analysis or using web-based tools. Although we will use a number of these to help illustrate points, the focus of the course will be on learning the underlying algorithms and exploratory data analyses and their applications, esp. in high-throughput biology.
Most of the lectures will be from research articles and slides posted online, with some material from the...
Optional text (for sequence analysis): Biological sequence analysis, by R. Durbin, S. Eddy, A. Krogh, G. Mitchison (Cambridge University Press),
No exams will be given. Grades will be based on online homework (counting 30% of the grade), 3 problem sets (given every 2-3 weeks and counting 15% each towards the final grade) and an independent course project (25% of final grade). The course project will consist of a research project on a bioinformatics topic chosen by the student (with approval by the instructor) containing an element of independent computational biology research (e.g. calculation, programming, database analysis, etc.). This will be turned in as a link to a web page. The final project is due by midnight, April 29, 2019. The last 2.5 classes will be spent presenting your projects to each other. (The presentation will account for 5/25 points for the project.)
Online homework will be assigned and evaluated using the free bioinformatics web resource Rosalind.
All projects and homework will be turned in electronically and time-stamped. No makeup work will be given. Instead, all students have 5 days of free “late time” (for the entire semester, NOT per project, and counting weekends/holidays). For projects turned in late, days will be deducted from the 5 day total (or what remains of it) by the number of days late (in 1 day increments, rounding up, i.e. 10 minutes late = 1 day deducted). Once the full 5 days have been used up, assignments will be penalized 10 percent per day late (rounding up), i.e., a 50 point assignment turned in 1.5 days late would be penalized 20%, or 10 points.
Homework, problem sets, and the project total to a possible 100 points. There will be no curving of grades, nor will grades be rounded up. We’ll use the plus/minus grading system, so: A= 92 and above, A-=90 to 91.99, etc. Just for clarity's sake, here are the cutoffs for the grades: 92% = A, 90% = A- < 92%, 88% = B+ < 90%, 82% = B < 88%, 80% = B- < 82%, 78% = C+ < 80%, 72% = C < 78%, 70% = C- < 72%, 68% = D+ < 70%, 62% = D < 68%, 60% = D- < 62%, F < 60%.
Students are welcome to discuss ideas and problems with each other, but all programs, Rosalind homework, problem sets, and written solutions should be performed independently . Students are expected to follow the UT honor code. Cheating, plagiarism, copying, & reuse of prior homework, projects, or programs from CourseHero, Github, or any other sources are all strictly forbidden and constitute breaches of academic integrity (UT academic integrity policy) and cause for dismissal with a failing grade.
The final project web site is due by midnight April 29, 2019.
- How to make a web site for the final project
- Google Site: https://support.google.com/sites/answer/153197?hl=en